docs: def annotate(self, text, annotators=None):
          """Return an AnnotatedDocument from the CoreNLP server.
  
          :param (str) text: text to be annotated
          :param (list[str]) annotators: a list of annotator names
  
          See a list of valid annotator names here:
            http://stanfordnlp.github.io/CoreNLP/annotators.html
  
          :return (AnnotatedDocument): an annotated document
          """
          doc_pb = self.annotate_proto(text, annotators)
          return AnnotatedDocument.from_pb(doc_pb)